J/ApJ/669/424 H2O maser emissions of IRAS 19134+2131 (Imai+, 2007)
The spatio-kinematical structure and distance of the preplanetary nebula
IRAS 19134+2131.
Imai H., Sahai R., Morris M.
<Astrophys. J., 669, 424-434 (2007)>
=2007ApJ...669..424I 2007ApJ...669..424I
ADC_Keywords: Infrared sources ; Masers ; Proper motions ; Space velocities
Keywords: masers - stars: AGB and post-AGB -
stars: individual (IRAS 19134+2131) - stars: kinematics -
stars: mass loss - stars: winds, outflows
Abstract:
Using the Very Long Baseline Array at six epochs, we have observed
H2O maser emission in the preplanetary nebula IRAS 19134+2131
(I19134), in which the H2O maser spectrum has two groups of emission
features separated in radial velocity by ∼100km/s. We also obtained
optical images of I19134 with the Hubble Space Telescope to locate the
bipolar reflection nebula in this source for the first time.
Description:
I19134 was imaged on UT date 2002 December 19 (GO program 9463) by the
Wide Field Camera (WFC) of the Advanced Camera for Surveys (ACS),
which has a plate scale of 0.05"/pi. Two dithered exposures of 338s
each were obtained through each of the two filters (F606W, pivot
wavelength lambda=0.599um and F814W, pivot wavelength lambda=0.806um).
The VLBA observations were made at six epochs spanning the period from
2003 January 4 to 2004 April 26 (BI 25 and 28)
Objects:
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RA (2000) DE Designation(s)
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19 15 35.2 +21 36 34 IRAS 19134+2131 = 2MASS J19153520+2136340
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 60 114 Parameters of the detected H2O maser features
table3.dat 72 20 Relative and absolute proper motions of
H2O maser features
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 10 A10 "YYYY/MM/DD" Date Observation date
12- 18 F7.2 km/s VLSR LSR velocity at the intensity peak
20- 27 F8.3 mas oRA Offset in right ascension (1)
29- 33 F5.3 mas e_oRA rms uncertainty on oRA
35- 41 F7.3 mas oDE Offset in Declination (1)
43- 47 F5.3 mas e_oDE rms uncertainty on oDE
49- 52 F4.2 Jy Ipeak Peak intensity of the feature (Jy/beam)
54- 57 F4.2 km/s DV Full velocity width of maser emission (2)
59- 60 I2 --- Feat ? Feature number listed in table3 (G1)
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Note (1): Position offset with respect to the delay-tracking center at
data correlation (RA=19:15:35.2150, DE=+21:36:33.900, J2000)
Note (2): The minimum is equal to the velocity spacing of a spectral
channel (0.21km/s).
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Feat Feature number (G1)
4- 10 F7.2 mas oRA Offset in right ascension from Feat#16 (1)
12- 16 F5.2 mas oDE Offset in Declination from Feat#16 (1)
18- 22 F5.2 mas/yr pmX Relative proper motion along X (2)
24- 27 F4.2 mas/yr e_pmX rms uncertainty on pmX
29- 33 F5.2 mas/yr pmY Relative proper motion along Y (2)
35- 38 F4.2 mas/yr e_pmY rms uncertainty on pmY
40- 44 F5.2 mas/yr PMX Absolute proper motion along X
46- 49 F4.2 mas/yr e_PMX rms uncertainty on PMX
51- 55 F5.2 mas/yr PMY Absolute proper motion along Y
57- 60 F4.2 mas/yr e_PMY rms uncertainty on PMY
62- 67 F6.2 km/s VZ Radial motion (3)
69- 72 F4.2 km/s e_VZ rms uncertainty on VZ (3)
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Note (1): Relative value with respect to the location of the
position-reference maser feature: IRAS 19134+2131:I2007 16.
Note (2): Relative value with respect to the motion of the
position-reference maser feature: IRAS 19134+2131:I2007 16.
Note (3): Relative value with respect to the adopted systemic velocity
VLSR=-67km/s.
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Global notes:
Note (G1): Identification of the maser feature. The feature is designated
as IRAS 19134+2131:I2007 NN, where NN is the ordinal source number
given in this column (I2007 stands for sources found by Imai et al.,
2007, IAU Symp, 242, and listed therein).
I2007 IRAS 19134+2131 NN in Simbad.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 15-Jan-2010